1. Field of the Invention
The invention relates to the field of retention systems for space capsules releasable from a spacecraft and, in particular, to a retention system that attaches to the peripheral edge of the capsule's reentry heat shield.
2. Description of Related Art
Releasing a satellite for placement in orbit or the ejecting of a reentry capsule requires reliable releasing mechanisms. Most such systems attach directly to the body of the satellite or capsule. For example U.S. Pat. No. 4,679,752 "Payload Deployment From Shuttle Employing An Ejection Restraint Device" by A Whittmann, et al. and U.S. Pat. No. 4,324,374 "Integrated Spacecraft And Cradle Structure" by A. Whittmann, et al., both disclose securing the satellite to a cradle within a space shuttle payload bay. The satellite is secured by means of ball trunnions held in place by pins, the withdrawing of the pins releasing the satellite from the cradle.
In U.S. Pat. No. 4,359,201 "Payload Deployment From Shuttle With Linear And Angular Velocity" by G. S. Thomson, et al. the satellite is also held in place by a series of ball fittings held in place by retractable pins. In U.S. Pat. No. 4,355,775 "Spacecraft Separation Apparatus" by E. R. Ganssle the satellite is secured in place by a series of hooks on the ends of bell cranks that engage brackets on the satellite. U.S. Pat. No. 4,506,852 "Payload Deployment From Launch Vehicle Using Canted Springs For Imparting Angular And Linear Velocities" by G. J. Adams, et al. the edge of a conical shaped adapter on the satellite mates with a separation ring on a cradle within the launch vehicle and which held together at their mating peripheral edges by means of a segmented clamp. Upon the actuation of explosive bolts, the segments separate and are pulled apart by springs.
All of the above systems are designed to release the satellite with specific linear and angular momentum and are not designed to release space capsules designed to re-enter the atmosphere of the earth or another planet, for that matter. Such capsules have may heat shields that serve as the mounting point, because the center of gravity of the capsule is close or within the heat shield area. In the past, the retention systems relied on explosive bolts that extended through the heat shield or back shell. This degraded the thermal performance of the heat shield or back shell by providing a thermal path through the structure.
Thus, it is a primary object of the invention to provide a system for releasably attaching a capsule to a spacecraft.
It is another primary object of the invention to provide a system for releasably attaching a capsule to a spacecraft that does not require struts or fasteners that penetrate the heat shield of the capsule and which provide a thermal path therethrough.
It is a further object of the invention to provide a system for releasably attaching a capsule to a spacecraft that is simple to install.
It is a still further object of the invention to provide for releasably attaching a capsule to a spacecraft that is highly reliable.